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Peripheral Nerve Stimulation in Diabetic Patients

This study has been completed.
Information provided by (Responsible Party):
Rigaud Marcel, MD, Medical University of Graz Identifier:
First received: December 2, 2011
Last updated: January 29, 2015
Last verified: January 2015

The prevalence of diabetes mellitus (DM) in industrialized countries is estimated to be about 7.3% and its incidence has been growing in recent years. The prevalence of diabetic neuropathy in the diabetic patient population is up to 50%. When limb surgery is necessary, it is reasonable to assume that diabetic patients will benefit from a peripheral regional anesthesia because of the severe comorbidities associated with DM. On the other hand, the use of regional anesthesia (RA) has generally not been recommended in patients with preexisting neuropathies mainly because of medical liability issues, as worsening neuropathy could be attributed to nerve damage caused by the regional anesthetic. The current state of the art of peripheral regional anesthesia for the identification of correct placement of an injection needle suitably close to the target nerve is to elicit a motor response by current injection through the needle. Constant reduction of the current as the nerve is approached ensures close proximity so that an effective nerve block is obtained when the local anesthetic is delivered through the needle, and absence of a motor response at 0.3 mA is generally accepted as a safety marker to avoid harmful intraneural injection. An important deficit in our understanding is whether diabetic neuropathy influences the stimulation parameters for peripheral nerve stimulation (PNS), possibly decreasing safety.

The currently proposed research is guided by the hypothesis that nerves in patients with DM are more resistant to stimulation and the current thresholds for PNS have to be set much higher to prevent injections from occurring within the epineurium. The investigators will examine the effect of DM on nerve excitability in a blinded, prospective, observational case control trial. Accordingly, the investigators have defined following aims:

Specific Aim 1: To characterize the required stimulation current in patients with and without diabetes mellitus.

Specific Aim 2: Follow-up to examine if the rate of adverse neurologic events is higher in diabetic patients.

Specific Aim 3: Guided by the results, formulate recommendations for the performance of regional anesthesia in patients with a history of DM.

These experiments will provide better understanding of the needle-current-nerve relationship during peripheral nerve stimulation. Findings from this study will have a major impact on patient safety, especially in the subgroup with preexisting neuropathy, undergoing regional anesthesia.

Condition Intervention
Diabetic Polyneuropathy
Procedure: peripheral nerve stimulation

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Prospective
Official Title: Influence of Diabetic Neuropathy on Current Settings During Peripheral Nerve Stimulation in Regional Anesthesia

Resource links provided by NLM:

Further study details as provided by Medical University of Graz:

Primary Outcome Measures:
  • Minimal current threshold for distal motor response at needle tip nerve contact [ Time Frame: 18 months ]

Biospecimen Retention:   Samples With DNA
  • blood samples
  • any material from surgical resections

Enrollment: 124
Study Start Date: January 2012
Study Completion Date: December 2013
Primary Completion Date: December 2013 (Final data collection date for primary outcome measure)
Groups/Cohorts Assigned Interventions
Diabetes Mellitus (DM)
Patients with diagnosed diabetes mellitus type 1 or 2 undergoing surgery of the lower limb and are receiving regional anesthesia with peripheral nerve stimulation
Procedure: peripheral nerve stimulation
defining the minimal current threshold for distal motor response
Control (C)
Patients with no history of diabetes mellitus Type 1 or 2 undergoing surgery of the lower limb and are receiving regional anesthesia with peripheral nerve stimulation
Procedure: peripheral nerve stimulation
defining the minimal current threshold for distal motor response


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Surgical patients scheduled for lower limb surgery and are eligible for a popliteal sciatic nerve block

Inclusion Criteria:

  • Patients of both sexes
  • age more than 18 years
  • American Society of Anesthesiology status 1 to 4
  • signed informed consent

Exclusion Criteria:

  • Pregnancy
  • Allergies to local anesthetics
  • Unwillingness or incapability to sign informed consent
  • Any preexisting neurological deficit of the lower limb that cannot be attributed to diabetic neuropathy
  • Ongoing dual anti-platelet therapy
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Please refer to this study by its identifier: NCT01488474

Medical University of Graz
Graz, Austria, 8036
Sponsors and Collaborators
Medical University of Graz
Principal Investigator: Marcel Rigaud, PD, MD Medical University of Graz
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Rigaud Marcel, MD, Principal Investigator, Medical University of Graz Identifier: NCT01488474     History of Changes
Other Study ID Numbers: KLI 135
Study First Received: December 2, 2011
Last Updated: January 29, 2015

Keywords provided by Medical University of Graz:
regional anesthesia
peripheral nerve stimulation
diabetic neuropathy

Additional relevant MeSH terms:
Diabetic Neuropathies
Peripheral Nervous System Diseases
Neuromuscular Diseases
Nervous System Diseases
Diabetes Complications
Diabetes Mellitus
Endocrine System Diseases
Central Nervous System Depressants
Physiological Effects of Drugs processed this record on April 28, 2017